An important objective in the development of vacuum cleaner filter bags resides in increasing the serviceable life of the filter bags. The serviceable life over which a vacuum cleaner filter bag can be used until it is filled with dust and/or the pores of the filter material are blocked is intended to be as long as possible, a high suction performance of the vacuum cleaner being sought at the same time over this period of time. Various approaches are known from the state of the art for achieving this objective.
In order to avoid blockage of the filter material forming the bag wall over a longer period of time, EP 0 960 945 discloses a multilayer bag wall construction in which a coarse filter layer is disposed in front of a fine filter layer in the air flow direction.
A vacuum cleaner filter bag is known from WO 2007/059939, which, in its interior, has a deflecting device disposed in the region of the inlet opening for deflecting the air flow entering through the inlet opening. Furthermore, an air-permeable material layer is provided in the interior of the filter bag and is not connected to the filter bag on at least one part of the edge.